Field of the Invention
The present technique relates to an optical characteristic measurement system that can measure optical characteristics, and a calibration method for the optical characteristic measurement system.
Description of the Background Art
There is a need for measuring the feeble light emitted by a photosensitizing substance in order to evaluate characteristics of a material or a reagent including the substance. For example, Japanese Patent Laying-Open No. 09-159604 discloses a singlet oxygen measurement apparatus that can measure even a sample including a photosensitizing substance having a light absorption characteristic with respect to an arbitrary wavelength in a range of an ultraviolet region to a visible region, and a sample that is directly and indirectly unstable with respect to the light and available only in a small amount.
In addition, Japanese Patent Laying-Open No. 09-292281, International Publication No. 2010/084566 and Japanese Patent Laying-Open No. 2011-196735 disclose a measurement apparatus and a measurement method for measuring the quantum efficiency indicating a ratio between an amount of photons absorbed by a sample including a fluorescent substance and an amount of photons of fluorescence generated from the sample.
In the singlet oxygen measurement apparatus disclosed in Japanese Patent Laying-Open No. 09-159604, a liquid nitrogen cooling-type germanium detector is used to increase a detection sensitivity. By cooling a detection element with liquid nitrogen or the like, the detection element can be stabilized and a detection dynamic range can be enlarged. On the other hand, in order to cool the detection element with liquid nitrogen, a few hours preparation including precooling and the like is required before the actually usable state is achieved, and thus, this singlet oxygen measurement apparatus is not practical.